Fair warning: if you ever thought there was nothing particularly interesting with optical viewfinders, prepare to have your misconception corrected by [volzo] with this deep-dive into camera-aiming aids that leads to an interesting hybrid smartphone viewfinder.
For most of us, the traditional optical viewfinder is very much a thing of the past, having been supplanted by digital cameras and LCD displays. But some people still want to frame a photograph the old-fashioned way, and the optical principles that make that possible are actually a lot more complicated than they seem. [volzo]’s blog post and video go into a great deal of detail on viewfinder optics, so feel free to fall down that rabbit hole — it’s worth the trip. But if you’d rather cut to the chase, the actual viewfinder build starts at about the 23:00 mark in the video.
The design is an interesting combination of lenses and beamsplitters that live in a 3D-printed enclosure. The whole thing slips over one end of a smartphone and combines an optical view of the scene that corresponds to the camera’s field of view with a small digital overlay from the phone’s screen. The overlay is quite simple: just some framing gridlines and a tilt indicator that’s generated by a little Android app. But it’s clear that much more information could be added now that [volzo] has all the optical issues sorted out.
We appreciate this deep dive into something that appears to be mundane and outdated, which actually proves to be non-obvious and pretty interesting. And if you have any doubt about the extreme cleverness of the camera engineers of yore, look no further than this sort-of solar-powered camera from the 1960s.
Continue reading “Interesting Optical Journey Results In Hybrid Viewfinder For Smartphones” →
When faced with what to build from the trimmings of the walnut tree in her yard, [Amy Qian] decided to build a headless travel ukulele. [via MAKE:]
Headless instruments relocate the tuners to the body of the instrument, and [Qian] had to do a fair bit of trimming and whittling on the body to make the tuners fit just right and still be operable via four scoops cut into the sides. After some initial troubles with the amount of friction on the strings produced by the mandrel, she replaced it with a set of ball bearings and a holder she machined out of aluminum.
We love how [Qian]’s extensive build log goes through the entire process of making this diminutive instrument from trimming dead walnut branches to building a playable instrument. Little details like the maple strip in the neck and the cocobolo accents really take this far beyond the cigar box instruments that start many down the path of luthiery.
Looking for more musical hacks? How about this set of Commodore 64s turned into an accordion or this Baguette Theremin?
There’s no doubt that the 7-segment display is a gold standard for displaying lighted digits. But what about a throwback to an older system of displaying numbers — Cistercian? With thirty-one 0805 LEDs, [Josue Alejandro] made a simple module displaying a single Cistercian digit (any from 0-9999).
The first iteration used castellated edges and required a significant number of GPIO, so on the next rev, he switched to a serial-to-parallel converted from Lumissil (IS31FL3726A). A diffuser and spacer were printed from PLA and made for an incredibly snazzy-looking package.
Of course, it couldn’t stop there, and a third revision was made that uses SK6812 Neopixels, allowing full RGB capability. All the design documents, layout files, and incredibly detailed drawings are available on GitHub. What makes this incredibly handy is having a module you can easily add to a project. Perhaps even as a component in an escape room in a box that would allow you to flash multiple numbers. Or perhaps as a stylish clock. We’d even go so far as to challenge someone to create a calculator by combining several of these modules with this keypad.
Northwestern University’s Embedded Electronics Class delivered a bumper crop of ESP-32 projects this year. The student teams recorded their progress on hackaday.io with project descriptions, logs, BOMs, diagrams, photos, and videos to share with other makers. While all utilized the web connection that the ESP32 offers some teams chose to use ESP32 Cams to incorporate photos, video, and computer vision. We love the variety of projects the teams created, some customized versions of consumer products and others new types of smart-devices. Continue reading “ESP32 Projects From Northwestern University’s Embedded Electronics Class” →
Join us on Wednesday, December 14 at noon Pacific for the Battery Engineering Hack Chat with Dave Sopchak!
Of all the things driving technology forward, you’d have to say that the ability of chip makers to squeeze more complex circuits than ever onto silicon has to rank right up there. And while that’s no doubt true, it only tells a part of the story. For our money, though, the advancements in battery technology over the last 30 years or so are the real champ, because without compact, cheap, energy-dense batteries, almost none of the cool stuff we see today, from smartphones to electric vehicles, would be practical.
Battery technology has come a long way from the days when carbon-zinc and nickel-cadmium cells were kings. New chemistries, better materials and methods, and engineering improvements have all contributed to incredibly powerful, incredibly compact batteries that make applications nobody could have thought of just a few decades ago possible.
Dave Sopchak has been in the thick of battery engineering since taking a doctorate in electrochemistry from Case Western Reserve. Since then he has worked at several fuel cell start-ups, and is now working on a lithium-air battery that sounds really interesting. We’ve asked him to help us wrap up the 2022 Hack Chat series with a discussion on battery engineering, with a focus on upcoming technologies and advancements that could really put some power in your pocket.
Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, December 14 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.
Surveillance has become a ubiquitous part of modern life. Public spaces are dotted with CCTV cameras inside and out. Recent years have seen the technology spread to the suburbs with porch cameras spreading the eye of big tech and law enforcement ever further.
Outside of mere cameras, companies are rushing to develop all manner of new devices to surveil individuals, too. One such device intended to track students quickly drew the ire of scholars at Northeastern University, and the cohort fought back.
Continue reading “Students Rebel Against Heat-Sensing Crotch Monitor Surveillance Devices” →
It’s the holiday season, and what better way to celebrate than to carve out some generative snowflakes on your laser cutter? [Bleeptrack] has developed a web-based tool that creates generative snowflake ornaments which can be exported to SVG files ready-made for laser or vinyl cutting.
True to their namesake, each generated snowflake ornament is (very likely to be) unique, with multiple layers created that can be stacked on top of each other. [Bleeptrack] has showcased a few realizations, using semitransparent paper sandwiched between two top layer cutouts, made out of wood or cardboard.
The snowflakes are a great balance of minimal design while still being beautiful and rich in detail. They can be easily produced on any laser cutter or vinyl cutter that you might have handy. Source code is available on GitHub for those wanting to dive into the details of the web tool. Cutting one of your own would make a perfect addition to a Neodriver ornament or a tiny DOOM playing ornament. Video after the break!
Continue reading “Laser-Cutting A Flurry Of Generative Snowflakes” →